浅析特低渗油田注水效果存水率和水驱指数评价法

油田的类型各式各样,在进行油田开发的过程当中,工作人员也可以选取不同的方式进行实际的开发操作.其中,注水开发的工程是在油田开发系统当中常见的一种工程,它需要根据油田的具体情况以及相关的参数,对油田注水的效果进行综合性评价之后,才可以将注水开发工程的效率进行大幅度的提升.一般情况下在进行油田开发工作时,特低渗透油田均是使...     

量子点材料在发光二极管中的应用前景

量子点(QD)发光材料具有发射频率随尺寸变化而改变、发射线宽窄、发光量子效率相对较高以及超高的光稳定性和溶液处理的特性.在过去的20年间,无机发光体已经被广泛应用于光电子学和生物医学等领域.其中,来自于中国和美国的研究人员已经深入地研究了高质量的多色量子点发光二极管(QD-LEDs)器件的物性,奠定了这些器件性能改进和优化的基石.     

常用液位检测方法的研究

介绍了几种目前在工业生产领域中比较新的液位检测方法,从测量原理、优缺点等方面做出了分析和比较,给出了典型的测量电路,并指出了液位检测的发展趋势.     

煤矿井下排水泵监控系统的设计

根据煤矿的实际生产情况,介绍了一种模块化的井下排水泵监控系统的设计。该系统采用AVR单片机ATmega16作为微处理器,能实时采集排水泵的运行参数、自动控制水泵及排淤装置的启动和停止、监控井下水仓的水位,并具有水位超限自动报警功能;采用单片机控制与PC监视相结合的方式,使地面调度室能随时监控排水泵的运行状况,当排水泵的参数超限时,可在地面远程操作排水泵。实际应用表明,该系统运行可靠、开发成本低、可移植性强。     

提高常规湿法炼锌铜直收率的实践

常规湿法炼锌工艺由于铜的浸出率较低,导致铜直收率偏低。通过采取提高液固比、提高中性浸出酸度和对中性浸出液酸化等措施,提高了铜浸出率,减少了铜的水解损失,进而提高了铜直收率。     

Synthesis of colloidal LaF3： 0.04Yb^3＋, 0.01Er^3＋ nanocrystals with green upconversion luminescence

A synthesis of LaF3：0.04Yb^3＋,0.01Er^3＋ nanocrystals with oleic acid as a capping ligand was presemed. The X-Ray Diffraction （XRD） pattern indicated that the power was a single hexagonal phase. Transmission Electron Microscopy （TEM） demonstrated that the average size of the nanocrystals was less than 10 nm, with a narrow size distribution. The nanocrystals were dispersible in nonpolar solvents and form a fully transparent colloidal solution, and the solution was stable for several months without any aggregates. The Yb^3＋-Er^3＋ codoped nanocrystal colloidal solution exhibited a bright green upconversion fluorescence under 980 nm excitation from a diode laser. The nanocrystals were potentially applicable in biolabeling and bioimaging.     

表面修饰的CdS半导体超微粒子的光学性质研究

由于半导体超微粒子(1—100nm)存在着显著的量子尺寸效应,使得它们的光物理和光化学迅速成为目前非常活跃的研究领域。当半导体超微粒子尺寸减小时,它们的吸收光谱和发射光谱发生兰移,同时引起其价带和导带形成一系列分立的能级。另外,由于这些超微粒子的尺寸很小,拥有相对大的表面积,因此在粒子表面存在着许多表面缺陷,严     

Synthesis and Upconversion Luminescence of LaF3 ： Yb^3＋ , Er^＋/SiO2 Core/Shell Microcrystals

LaF3：Yb^3＋ , Er^＋ microcrystals were synthesized by a hydrothermal method, and then, the LaF3： Yb^3＋ , Er^＋ microcrystals were coated with silica. Phase identification of LaF3： Yb^3＋ , Er^＋ and LaF3： Yb^3＋ , Er^＋/SiO2 was performed via XRD. The TEM image showed that the size of LaF3： Yb^3＋ , Er^＋ was 150 nm and LaF3： Yb^3＋ , Er^＋/SiO2 presented clearly a core/shell structure with 20 nm shell thickness. The upconversion spectra of LaF3： Yb^3＋ , Er^＋ and LaF3： Yb^3＋ , Er^＋/SiO2 in solid state and in ethanol were studied with a 980 nm diode laser as the excitation source. The upconversion spectra showed that the silica shell had little effect on the properties of fluorescence of the LaF3：Yb^3＋ , Er^＋ microcrystals. At the same time, the green luminescence photo of LaF3： Yb3＋, Er3＋/SiO2 in the PBS buffer was obtained, which indicated that the LaF3： Yb^3＋ , Er^＋/SiO2 could be used in biological applications.     

分散在SiO2中的Y2O3:Eu3+纳米晶的光学性质

采用正硅酸乙酯为SiO2的先驱体,采用Sol-Gel法制备了分散在SiO2基质中的Y2O3Eu3+纳米晶发光材料,研究了材料在不同退火温度下Eu3+稀土离子的光学性质.发射光谱表明随着退火温度的不同,光谱发生了明显变化,并特别地分析了样品在1300℃退火温度下,平均粒径50 nm颗粒样品的发光特性,实验结果表明,在这种发光材料中Eu3+占居4种格位和1种表面态.     

Site Selective Spectroscopy of Suffactant－Assembled Y2O3：Eu Nanotubes

Y2O3:Eu nanotubes were synthesized by a surfactant assembly mechanism. Under ultraviolet-light excitation,the nanotubes present luminescence properties different from that of Y2O3:Eu nanoparticles. The peak position of the charge transfer band in excitation spectra varies with the monitoring emission peaks, while the emission spectra are dependent on the excitation wavelength. Laser selective spectroscopy was performed to distinguish the local symmetries of the Eu^3 ions in the nanotubes. The results of laser-selective excitation indicate that the emission centers near the surface of nanotube wails exhibit inhomogeneously broadened spectra without spectral structures while the two sites (site B and site C) inside the nanotube walls present resolved spectral structures. It is concluded by the number and peak positions of the spectral lines that the sites B and C possess different site symmetries.